This invention relates to instrumentation for invading body canals non-destructively and with a minimum of trauma, and more particularly, to the interface between the instruments and body tissue during dynamic ingress and egress of surgical instrumentation into the canals.
It has been the direction of the prior art to fashion the surface structure of instrumentation used for the non-destructive invasion of body canals with a very slippery surface to facilitate ingress of the instrumentation into the body canal. The resulting slippery surface also produces low friction during egress of the instrumentation from the body canal.
As set forth in detail in U.S. application Ser. No. 09/184,331, filed Nov. 2, 1998, entitled xe2x80x9cBody Canal Intrusion Instrumentation Having Bidirectional Coefficient of Surface Friction with Body Tissuexe2x80x9d, and which is hereby incorporated by reference, it has been found that the ingress of the medical device or other instrumentation into a desired body site can be facilitated by the utilization of a surface structure on the device having a bi-directional coefficient of friction with respect to the tissue within the body cavity or canal that is engaged by the device during ingress. For example, it has been found that naturally occurring peristaltic contractions tend to grasp and carry the device toward the desired work site. This significantly decreases the risk of puncture by the device, as well as reduces the time required by the surgeon for entry and positioning of the device at the desired work site. These advantages are particularly important during procedures such as the insertion of a gastric or jejungal feeding tube through the esophagus and into or through the stomach or small intestine.
Large flaps or barbs have been used on the outside surface of catheters and related devices for the purpose of stabilizing or anchoring the device within the body canal. These flaps or barbs are designed to prevent both ingress and egress of the device once the device has been positioned at the desired location within the body canal. These flaps or barbs are typically rigid, and are attached to the outside of the device in a hinged manner. However, these devices can be very traumatic to the tissue of the body canal, and can be very uncomfortable to the patient, when manipulated within the body or upon egress from the body canal.
In view of the above, there is a need for a medical device or other instrumentation having a series of flaps that function in a bi-directional manner to engage the tissue of the body canal so as to assist with ingress of the device, but which will permit egress of the device without causing trauma or discomfort to the patient.
The foregoing problems are solved and a technical advance is achieved in a medical device, such as a gastrointestinal catheter, for use in delivering fluid-like materials to the gastrointestinal tract. Such fluid-like materials could include feeding materials, drugs, contrast materials or saline.
The illustrative embodiment of the present invention is directed to a nasal-jejunal feeding tube having an arrangement of flaps cut from the outer surface of the catheter and configured so as to not readily adhere to the catheter outer surface. The arrangement of flaps are also configured so as to resist egress to the degree that allows the body to propel the device forward, yet will allow the device to be removed from the body without the flaps causing significant trauma, such as inflammation, to the tissues of the body canal, and thereby minimizing or eliminating patient discomfort.
The preferred embodiment illustrated herein comprises a 14 FR nasal-jejunal feeding tube having a minimum overall length of 154 cm. A series of flaps are formed on the outer surface of the distal 50 cm of the catheter portion. Four longer flaps are formed near the distal end of the feeding tube, and are arranged about the perimeter of the feeding tube at approximately equal intervals (i.e., at 90xc2x0 intervals with respect to each other). A number of shorter flaps are distributed along the length of the feeding tube inwardly or proximally from the four longer flaps. These shorter flaps alternate along opposite sides of the feeding tube at approximately 2 cm intervals for the distal 50 cm of the catheter. The feeding tube also includes several apertures distributed along the distal portion of the catheter. These feeding tube apertures alternate along opposite sides of the feeding tube at approximately 2 cm intervals, and are generally disposed at 900 intervals with respect to the shorter flaps.